Appearance.

1. If you see a ball valve with a down trunnion, it must be trunnion mounted ball valve, because floating Ball valve dont's have.

2. When a ball valve have Seat injection fitting, there's no doubt it's a trunnion ball valve. but you Can't say it must be a floating ball valve, because very small size turnnion Ball valve also don't have seat injection fitting, such as 2″ 150LB.

Working Priciples.

1. the ball of a floating Ball ball is movable, it moves slightly after the medium give pressure to it, Then the ball touched closely with the seat to seal. but in a trunnion mounted Ball valve, the ball is fixed, don't move. The medium push the seat move and Closely touched with the ball, that's the way of sealing.

Design and Usage.

1. Trunnion mounted ball Valve have a lower turnnion to fix the ball while floating ball valve not.

2. Floating ball valve is Usually for small size up to 10″ and low pressure, while trunnion type reaches Max 60″,  pressure up to 2500LB.

3. Tunnion mounted ball Valve have double block and bleed function, but a floating type can't. Trunnion Ball valve could block the medium from both upstream and downstream, it's Totally bidirectional design. When the pressure in the valve cavity is Higher than the pretightening force,  it will push the seat move to Relief the pressure, so to keep safe

4. the torque of a trunnion Ball valve is smaller than a same size and pressure floating ball valve.

5. Trunnion ball valve have Emergency seat injection fitting for size bigger than 4″ while floating ball Valve not.

6. the sealing of trunnion Ball valve is much more reliable than floating type, the seat was inserted into A steel retainer, and the retainer surported by the spring, so to keep the seat with enough  pretightening force. Even the sealing face wearing out, It still seal good.

these just my knowledge about floating and trunnion mounted ball valves,  if you have any idea, Welcome to contact us.

 

Full Welded Ball Valve

Design Features

1.the valve seat is embedded with flexible seal ring(optional Triangular ring) to ensure good seal.
2.the valve seat is provided with a preloaded spring that is adaptive to the Variation of pressure and temperature.
3.Integral valve with welded valve body, free of external leakage
4.Fire resisting construction design.
5.the most advanced support plate structure both at home and abroad is adopted for large diameters to increase the service life and reduce the operating Torque of valve. Thus, the service life of valves is greatly extended.
6.Optional underground design
7.Full bore opening for pigging conveniently with small flow resistance and High flow capacity and good flow characteristics.
8.the valve ball can completely enclose the valve seat when the valve is Opened, so the impurities in the medium will not be flushed to the valve seat or the packing surface of valve body and the valve serice life is extended.

   

Product Range

Size/Rating: NPS 2"~60"(DN15~DN1500)
Rating: CLASS 150~1500LB
End Connection: Flange, weld

   

Design Standards

Basic Design: API 6D/ISO 14313
Structure Length: ASME B16.10/API6D
End Connection: ASME B16.5,MSS SP-44/ASME B16.47, ASME B16.25
Test & Inspection: API 6D